Millon Clinical Multiaxial Inventory
The Millon Clinical Multiaxial Inventory-III (MCMI-III) is a psychological assessment tool intended to provide information on psychopathology, including specific disorders outlined in the DSM-IV. It is intended for adults (18 and over) with at least an 8th grade reading level who are currently seeking mental health services. The MCMI was developed and standardized specifically on clinical populations (i.e. patients in psychiatric hospitals or people with existing mental health problems), and the authors are very specific that it should not be used with the general population or adolescents. However, there is a strong evidence base that shows that it still retains validity on non-clinical populations, and so psychologists will often administer the test to members of the general population.
The MCMI differs from other personality tests in that it is based on theory and is organized according to a multiaxial format. Updates to each version of the MCMI coincide with revisions to the DSM.
The test is modeled on four scales
- 14 Personality Disorder Scales
- 10 Clinical Syndrome Scales
- 5 Correction Scales: 3 Modifying Indices (which determine the patient's response style and can detect random responding); 2 Random Response Indicators
- 42 Grossman Personality Facet Scales (based on Seth Grossman's theories of personality and psychopathology)
- 1 History of the MCMI
- 2 Theoretical Anchoring
- 3 Current scale composition
- 4 Psychometric properties
- 5 Scoring system
- 6 Interpretation
- 7 See also
- 8 References
- 9 External links
History of the MCMI
In 1969, Theodore Millon wrote a book called Modern Psychopathology, after which he received many letters from students stating that his ideas were helpful in writing their dissertations. This was the event that prompted him to undertake test construction of the MCMI himself. The original version of the MCMI was published in 1977 and corresponds with the DSM-III. It contained 11 personality scales and 9 clinical syndrome scales.
With the publication of the DSM-R, a new version of the MCMI (MCMI-II) was published in 1987 to reflect the changes made to the revised DSM. The MCMI-II contained 13 personality scales and 9 clinical syndrome scales. The antisocial-aggressive scale was separated into two separate scales, and the masochistic (self-defeating) scale was added. Additionally, 3 modifying indices added and a 3-point item-weighting system introduced.
The current version, the MCMI-III was published in 1994 and reflected revisions with DSM-IV. This version eliminated the aggressive and self-defeating personality scales and added scales for depressive and PTSD bringing the total number of scales to 14 personality scales, 10 clinical syndrome scales, and 5 correction scales. The previous 3-point item-weighting scale was modified to a 2-point scale. Additional content was added to include child abuse, anorexia and bulimia. The Grossman Facet scales are also new to this version. The MCMI-III is composed of 175 true-false questions that reportedly takes 25–30 minutes to complete.
The MCMI-III is based on evolutionary theory and is composed of four main domains/spheres:
Three polarities provide the continuum for each of the first three domains:
Current scale composition
The MCMI-III contains a total of 28 scales broken down into 24 clinical scales (personality and clinical syndrome scales) organized by severity. In addition, the MCMI-III features the addition of 42 Grossman Facet scale scores described in detail below.
14 Personality Disorder Scales correspond with Axis II diagnoses of the DSM-IV. They describe more pervasive conditions. They are broken down further into 11 basic, clinical personality patterns (Scales 1-8B) and 3 severe personality pathology scales (S-P).
Clinical syndrome scales
10 Clinical Syndrome Scales correspond with Axis I diagnoses of the DSM-IV. Similar to the personality scales, the 10 clinical syndrome scales are broken down into 7 moderately severe scales (A-R) and 3 severe clinical syndrome scales (SS-PP).
The modifying indices consist of 3 scales: the Disclosure Scale (X), the Desirability Scale (Y) and the Debasement Scale (Z).
These scales are used to determine a patient's response style, including whether they presented themselves in a positive light (elevated Desirability scale) or negative light (elevated Debasement scale). The Disclosure scale measures whether the person was open in the assessment, or if they were unwilling to share details about his/her history.
Random response indicators
In general, the Invalidity Scale (V) contains a number of improbable items which may indicate questionable results if endorsed. The Inconsistency Scale (W) detects differences in responses to pairs of items. The more inconsistent pairs of items, the more confident the examiner can be that the person is responding randomly.
Grossman Facet Scales
Each of the 14 personality scales has three of these facet scales, which were designed to enhance interpretation of the clinical personality patterns and severe personality pathology scales.
The MCMI-III was updated in 2008, with a new norming sample of 752 individuals with a wide variety of clinical disorders (52.8% female; 76% Caucasian). The scale development stage consisted of 600 of these individuals (48.8% male; 84% Caucasian), and the cross-validation stage consisted of the remaining 398 individuals (49.5% male, 81.7% Caucasian).
Test construction underwent three stages of validation, more commonly known as the tripartite model of test construction (theoretical-substantive validity, internal-structural validity, and external-criterion validity). Development was an iterative process, with each step reanalyzed each time items were added or eliminated.
The first stage was a deductive approach and involved developing a large pool of items; the number of items was reduced based on a rational approach according to the degree to which they fit the theory as well as elimination of items based on simplicity, grammar, content, and scale relevance.
Once the initial item pool was reduced, the second validation stage assessed how well items interrelated, and the psychometric properties of the test were determined. Internal consistency is the extent to which the items on a scale generally measure the same thing. Cronbach’s alpha statistics range from .66 (Compulsive) to .90 (Major Depression). Test-retest reliability is a measure of the stability of the measure, or the change over time. The higher the correlation, the more stable the measure is. Based on 87 participants, the test-retest reliability of the MCMI-III (5–14 days later) ranged from .82 (Debasement) to .96 (Somatoform) with a median coefficient of .91. These statistics indicate that the measure is highly stable over a short period of time; however, no long-term data are available.
The final validation stage includes convergent and discriminative validity of the test, which is assessed by correlating the test with similar/dissimilar instruments.
Positive predictive power is the likelihood of being right given a test positive, which ranged from .30 (Masochistic) to .81 (Dependent). Sensitivity, or the proportion of individuals that have a condition that are correctly identified ranged from .44 (Negativistic) to .92 (Paranoid).
Patients' raw scores are converted to Base Rate (BR) scores to allow comparison between the personality indices. The Base Rate scores are essentially where each score fits on a scale of 1-115, with 60 being the median score. Conversion to a Base Rate score is relatively complex, and there are certain corrections that are administered based on each patient's response style.
The Modifying indices are scored using a complex system in which the patient's responses in the other scales are compared and the raw and BR scores are taken from this. However, the Invalidity index is an exception to this and is not converted to a BR score.
Test results may be considered invalid based on a number of different response patterns on the modifying indices. The Disclosure scale is the only scale in the MCMI-III in which the raw scores are interpreted and in which a particularly low score is clinically relevant. A raw score above 178 or below 34 is considered to not be an accurate representation of the patient's personality style as they either over-or under-disclosed and may indicate questionable results.
The Invalidity Index is a measure of random responding, ability to understand item content, appropriate attention to item content, and as an additional measure of response style. The scale is very sensitive to random responding. Scores on this scale determine whether the test protocol is valid or invalid. A base rate score of 75 or greater on the Desirability or Debasement scales indicate that the examiner should proceed with caution.
For the Personality and Clinical Syndrome scales, base rate scores of 75-84 are taken to indicate the presence of a personality trait, or (for the Clinical Syndromes scales) the presence of a clinical syndrome. Scores of 85 or above indicate the persistence of a personality trait or a clinical syndrome.
- Millon Clinical Multiaxial Inventory-III (MCMI-III) FAQs, Q1: "When is it appropriate to use the MCMI-III test?"
- Millon, T.; Millon, C., Davis, R., & Grossman, S. (2009). MCMI-III Manual (Fourth ed.). Minneapolis, MN: Pearson Education, Inc.
- Millon Clinical Multiaxial Inventory-III (MCMI-III) - scales
- Millon, T. (2008). The logic and methodology of the Millon inventories. Cross-cultural personality assessment. In G. J. Boyle, G. Matthews, & D. H. Saklofske (Eds.). Sage handbook of personality theory and assessment. Vol. 2: Personality theory and assessment. Los Angeles, CA: Sage.
- Millon, T.; Millon, C., Davis, R., & Grossman, S. (2006). MCMI-III Manual (Third ed.). Minneapolis, MN: Pearson Education, Inc.
- Millon Clinical Multiaxial Inventory-III, at Pearson Education, Inc.